wp_insert_comment

	$comment_author = '';
	if ( isset( $_COOKIE[ 'comment_author_' . COOKIEHASH ] ) ) {
		$comment_author = $_COOKIE[ 'comment_author_' . COOKIEHASH ];
	}

	$comment_author_email = '';
	if ( isset( $_COOKIE[ 'comment_author_email_' . COOKIEHASH ] ) ) {
		$comment_author_email = $_COOKIE[ 'comment_author_email_' . COOKIEHASH ];
	}

	$comment_author_url = '';
	if ( isset( $_COOKIE[ 'comment_author_url_' . COOKIEHASH ] ) ) {
		$comment_author_url = $_COOKIE[ 'comment_author_url_' . COOKIEHASH ];
	}

	/**
	 * Filters the current commenter's name, email, and URL.
	 *
	 * @since 3.1.0
	 *
	 * @param array $comment_author_data {
	 *     An array of current commenter variables.
	 *
	 *     @type string $comment_author       The name of the current commenter, or an empty string.
	 *     @type string $comment_author_email The email address of the current commenter, or an empty string.
	 *     @type string $comment_author_url   The URL address of the current commenter, or an empty string.
	 * }
	 */
	return apply_filters( 'wp_get_current_commenter', compact( 'comment_author', 'comment_author_email', 'comment_author_url' ) );
}

/**
 * Get unapproved comment author's email.
 *
 * Used to allow the commenter to see their pending comment.
 *
 * @since 5.1.0
 *
 * @return string The unapproved comment author's email (when supplied).
 */
function wp_get_unapproved_comment_author_email() {
	$commenter_email = '';

	if ( ! empty( $_GET['unapproved'] ) && ! empty( $_GET['moderation-hash'] ) ) {
		$comment_id = (int) $_GET['unapproved'];
		$comment    = get_comment( $comment_id );

		if ( $comment && hash_equals( $_GET['moderation-hash'], wp_hash( $comment->comment_date_gmt ) ) ) {
			// The comment will only be viewable by the comment author for 1 minute.
			$comment_preview_expires = strtotime( $comment->comment_date_gmt . '+1 minute' );

			if ( time() < $comment_preview_expires ) {
				$commenter_email = $comment->comment_author_email;
			}
		}
	}

	if ( ! $commenter_email ) {
		$commenter       = wp_get_current_commenter();